Heating furnace



Nov. 20, 1928. 1,692,614

R. 3E. BlssELL HEATING FURNACE Filed. Nov. zo, 192s 2 Sheets-snaai 1 /NVE/vraff A50/Aka E fffa 45mm/EK Nov. 20, 1928.

` l 1,692,614 R. E. BxssELL lHEATING FURNACE Filed Nov. 20, 1925 .2 Sheets-Sheet 2 Patented Nov. 20, 1928.

UNITED LSTATES PATENT OFFICE.

RICHARD E. BISSELL, OF CLEVELAND HEIGHTS, OHIO, ASSIGNOR T THOMPSON PROD- UCTS, INCORPORATED, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

HEATING FURNACE.

Application filed November 20, 1925. Serial No. 70,234.

My invention relates to heating furnaces of the type in which articles are pushed into one end of the furnace one after another and progressively passed therethrough by a continuous or an intermittent movement until they reach a chute through which they are discharged by gravity-usually into a quenching bath.

n The interior of these furnaces has hereto fore been provided with one or more guideways for the articles, and which were suhstan- `tially horizontal. As a result of such position, the articles, which'usually form a column of considerable length, 'engage the guideway surfaces with a degree of frictional resistance,

such as makesit difficult sometimes to cause them to travel through the furnace, and even causes the column to buckle and the articles to jam, thus impeding or preventingtheir further progress. In fact it has been found that some types of articles could not be passed through such a furnace at all. f

The object of my invention is to overcom such'dcscribed difiiculties and this we' acc-omplish primarily by providing the heating chamber with guideways which are angular with respect to the horizontal, that is inclined downwardly from the front or feed-end of the furnace toward the back or discharge end thereof.

Furthermore, the invention contemplates effecting the progress of the pieces or articles through the furnace in such a manner that they will notloecome chilled by contact with -the cooler fumes or gases arising from the quenching bath, or by association with a zone of temperature which is below that required and which would produce ysuch chilling.

The said invention consists of means hereinafter fully described and particularly set forth in the claims;

The annexed drawings-and the following descriptionset forth in detail certain means embodying my invention, the disclosed means, however, constituting but one of the various mechanical forms in which the principle of the 'invention may be employed.

In said annexed drawings.:`

`Figure 1 represents an axialfvertical sec'.-y

.tion of a 4furnace embodying our invention,

showingparts in elevation.

Fig. 2 represents, upon an enlarged scale, a fragmentary part of such axial section and clearly illustrating the flap door of the chute.

Fig. 3 represents a fro nt elevation.

Fig. 4 represents a section taken upon the planes indicated by lines IV-IV in Fig. 1.

Fig. 5 represents a rea r elevation.

F igs. 6 and 7 represent sections similar to that of Fig. 4, showing modified forms of guidewavs.A

In the'illustrated embodiment of my invention, the heating receptacle 1 is provided with a horizontal heating chamber 2 having its front end enclosed by a suitable door 3 by `means of which accessv chamber, when desired.

may be had to saidy Near the rear end fluid 6. A. splash guard 6a in the nature of a damper, extends across the chute 4l; near the lower end thereof, being fixed at its rear edge Ato a rod 6b pivotally mounted in the chute.

A weighted arm 6c is secured to the rod 6" outside the chute to keep the guard in normally closed position.

The purpose of this guard is to prevent disturbances in the heatingchamber which might otherwise result from the gas ebulition when the hot quenching fluid; .1

pieces fall into the The rear end ofthe receptacle 1 is provided with a fixture 7 which is pivotally connected with a bracket 8 suitably secured upon a support or foundation 9, such connection being made hv a horizontal pin 10. 'l

The front end of the receptaclel is supported upon a screw 11 provided with a hand-wheel 12 and mounted in a suitable fixture 13.

Resting upon and sui floor 14 ofthe chamber 2 allel tubes 15 each of whi for the article to be heate tably secured to the is ay plurality of parch forms a guidewaj.Y d (in this ease shown to be poppet valves). The outer ends of these tubes are shown to be open and extend out of the receptacle, as shown in Fig. 1, and in the form shown in said figure, the inner ends thereof are open and ext up to the chute 4.

end adjacent but not Cil The receptacle normally occupies a position in which these guideways are at an angle to the horizontal, that is, they incline downwardly from the front or feeding end of the furnace, to the back or discharge` end, as shown, and such angularity may be changed by means of screw 1l, as will be readily seen.

Extending from the ends of the tubes or guideways 15 and to the chute 4, is a flat plate 16 whose upper surface is in alinement with the bottom surface of said tubes, forming a slideway to which articles may move from said tubes, without encountering anyy resistance other than frictional. The said surface inthe form of furnace illustrated is given a somewhat greater angularity than that of the guideways for the purpose hereinafter eX- plained.

Any suitable source is provided for heating the interior of the receptacle to the required temperature. In this particular case, I haveelected to illustrate the device as heated by electric power, suitable electric elements 17 being shown for this purpose.

The method of utilizing the above described furnace is as follows: The maximum angle at which the slideways may be tilted without causing gravity to overcome the frictional resistance between the articles and the ways while said articles are lying stationary in the latter and subject to the heating action of the chamber, is determined. This will, of course, vary with the character of the material of which the articles and ways and slide are made; the shape of such articles and the degree of heat imparted thereto, but may readily be determined empirically as will be understood. This maxi-Y mum angle is called the angle of repose.

Approximately this angle, preferably one slightly less, is then imparted tothe ways by means of the adjust-ing screw 11.

The articles are then pushed one 'by one into the front end of the respective ltubular guideways untilthey form in each anangu larly disposed column. As they progress through the ways, they increase in temperature until they reach the end thereof, emerge therefrom andy are. delivered to and discharged` across the plate 16, which, owing to its increased angularity, offers less frictional resistance to thel articles than to the slideways, and the force of gravity causes them to slide off the plate, into and through the chute 4 andinto the quenching bath.

Inasmuch as the column of articles lies substantially in its angle of repose, little resistance to its movement is encountered andwhich might otherwise taire place after the articles emerge from the tubes and approach Athe back and cooler wall of the furnace, such more or less comparatively cool fumes from i the evaporation of the quenching fluid.

It will be seen that it is possible thatthe column of-articles mightattain sufficient momentum after being moved by the introduction of one of same into the feedingend of the tube, to continue to overcome'the frictional resistance acting in such column, and cause the column to continue to move or avalanche, thus discharging the entire column by continuous and spontaneous movement, which of course under certain conditions would not allow the articles to remain in the furnace longenough to acquire the desired temperature.

It may therefore sometimes be desirable toadd a resistance or retarding device to the column which will supplement the frictional resistance of the guideways.

4To this end therefore an impeding element such as the closure 18 of properly determined weight and hinged at the top to the inner end of each tube, may be provided which will add the requisite amount of additional resistance to the column to provide for such a contingency.

It willbe understood that it may be necessary to vary the design of details of the furnace to handle articles of a specific' charactery or form. For example,'the variation of angularity of the plate' 16 from that of the slideways might in some cases be dispensed with entirely. i The broad principle involved in theprovision of an inclined slideway may also be applied to a non-tubular furnace and plain open guideways provided in V-shaped form, or circular grooves, as shown in Figs. 6 and 7, or of any other shape desired for any specific form of article.

The illustrated form of my invention is what I now consider the preferred form, in

l which the axis of the heating chamber is inclined and the slideways fixed to the bottom or floor thereof. It will be apparent, however, that the inainprinciple involved in the invention may' be applied toy a non-tilting furnace, the axis ofwhose heating chamber is horizontal and whose guideways may be placed within such Chamber in an inclined position, means being provided for varying y is changed.

I have also found that an angle of inclination of from fifteen to thirty degrees from the horizontal will include substantially all of the angles necessary for feeding all articles which it may be desired to heat in the described manner, that is by pushing in a column through the heating zone.

As illustrated in the drawing, the front or receiving end of the tubular guideways may be beveled so as to form an end surface lying in a plane cutting the tubes axes at, an acute angle. Such structure permits the articleto be readily inserted into the tubes and particularly where the diameter of the article is nearly that of the interior of the tube.

What I claim is:

1. A furnace for simultaneously heating a plurality of unit pieces, and having a heated chamber with a guideway therein at an angle to the horizontal and adapted to receive and guide the pieces, a discharge chute adjacent to the inner end of said guideway and within the heating chamber; and a slideway between the lguideway and chute of greater angularity to the horizontal than the guideway and of greater length than the length of the unit piece being heated.

2. A heating receptacle for simultaneously heating a pluralit of unit pieces and having a guideway therein at an angle to the horizontal slightly less than'the angle of repose and adapted to receive and guide the pieces; and means at the lower end of the guideway adapted to support the column of pieces against a slight displacing force.

3. The combination specified in claim 2 in which the means supporting the column of pieces consists of 4a hinged member adapted to engage the lowermost piece. v

4. The method of heating metal parts which consists in supporting a plurality of such parts in alinement and at an angle downwardly inclined to the horizontal slight-ly less than the angle of repose, and feeding the articles downwardly by force applied to the upper end of the column while subjecting 'them to heat.'

5. The method of heating a plurality of parts, which consists in supporting a plurality of such parts in alignment and at an angle downwardl inclined relative to the horizontal and shghtly less than the angle of repose, feeding the aligned column of parts downwardly by force applied to the upper end of the column to progressively subject the aligned parts to heat, and applying friction to a part at the lower end of said column to prevent accidental displacement of the parts in said column.

6. Inl combination, in a furnace, a heating chamber, a guideway therein normally inclined downwardly \at an angle to a horizontal plane and of less magnitude than the angle of repose of articles to be heated and adapted to receive and guide in alignment a plurality of articles to be heated, and means for .varying the inclination of said guideway.

7. In combination, in a furnace, a heating chamber, a guideway therein normally inclined to a horizontal plane and adapted to receive and guide in alignment a plurality of articles to be heated, said guideway having a surface approximately conforming to the contour of a part of the article to be heated, whereby a plurality of said articles may be maintained in substantially axial alignment, and means for varying the inclination of said guideway.

8. In combination, in a furnace, a heating v chamber, a plurality of guideways therein,

each of which is normally inclined to a horizontal plane and provided with a substantially curved surface, each of said guideways being adapted to receive and guide in alignment a plurality of articles to be heated, and means for varying the inclination of said guideways.

9. In combination, in a furnace, a heating chamber, a plurality of substantially parallel guideways therein, each of which is normally inclined to a horizontal plane and of substantially tubular form, each of said guideways being adapted to receive and guide in alignment a plurality of articles to be heated, a discharge chute common to said guideways; and means for varying the inclination of said guideways.

10. In combination, in a furnace, a heating chamber, a guideway therein normally inclined to a horizontal plane and adapted to receive and guide in alignment a plurality ofv 'articles to be heated, said guideway being adapted to receive and guide in alignment a plurality of articles to be heated, and a discharge chute disposed adjacent the rear end of the chamber for receiving the articles as they leave the guideway and for delivering the articles to a bath.

12. In combination, in a furnace, adapted to progressively heat a plurality of parts, means defining a heated chamber, a guide- Way in said chamber adapted tobe iiisposed 5 at an angle downwardly inclined relative to the horizontal and slightly less than the angle of repose of the parts to be heated, a discharge chute associated with the lower end of said guideway, and a' slideway between the guideway and chute of greater angularity to the 10 horizontal than the gideway.

Signed by me thispth day of October,

RICHARD E. BISSELL. 

